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		<title>three.js webgl - instancing - modified</title>
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		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - webgl instancing - modified
		</div>

		<script type="module">

			import * as THREE from '../build/three.module.js';

			import Stats from './jsm/libs/stats.module.js';

			let camera, scene, renderer, stats;

			let mesh;

			const dummy = new THREE.Object3D();

			const amount = 8;
			const count = Math.pow( amount, 3 );

			init();
			animate();

			function init() {

				renderer = new THREE.WebGLRenderer( { antialias: false } ); // false improves the frame rate
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				document.body.appendChild( renderer.domElement );

				renderer.outputEncoding = THREE.sRGBEncoding;

				scene = new THREE.Scene();

				camera = new THREE.PerspectiveCamera( 40, window.innerWidth / window.innerHeight, 1, 100 );
				camera.position.set( 0, 0, 20 );

				new THREE.BufferGeometryLoader().load( 'models/json/suzanne_buffergeometry.json', function ( geometry ) {

					const instanceColors = [];

					for ( let i = 0; i < count; i ++ ) {

						instanceColors.push( Math.random() );
						instanceColors.push( Math.random() );
						instanceColors.push( Math.random() );

					}

					geometry.setAttribute( 'instanceColor', new THREE.InstancedBufferAttribute( new Float32Array( instanceColors ), 3 ) );

					geometry.computeVertexNormals();

					geometry.scale( 0.5, 0.5, 0.5 );

					//console.log( geometry );

					//

					new THREE.TextureLoader().load( 'textures/matcaps/matcap-porcelain-white.jpg', function ( texture ) {

						texture.encoding = THREE.sRGBEncoding;

						const material = new THREE.MeshMatcapMaterial( { color: 0xaaaaff, matcap: texture } );

						const colorParsChunk = [
							'attribute vec3 instanceColor;',
							'varying vec3 vInstanceColor;',
							'#include <common>'
						].join( '\n' );

						const instanceColorChunk = [
							'#include <begin_vertex>',
							'\tvInstanceColor = instanceColor;'
						].join( '\n' );

						const fragmentParsChunk = [
							'varying vec3 vInstanceColor;',
							'#include <common>'
						].join( '\n' );

						const colorChunk = [
							'vec4 diffuseColor = vec4( diffuse * vInstanceColor, opacity );'
						].join( '\n' );

						material.onBeforeCompile = function ( shader ) {

							shader.vertexShader = shader.vertexShader
								.replace( '#include <common>', colorParsChunk )
								.replace( '#include <begin_vertex>', instanceColorChunk );

							shader.fragmentShader = shader.fragmentShader
								.replace( '#include <common>', fragmentParsChunk )
								.replace( 'vec4 diffuseColor = vec4( diffuse, opacity );', colorChunk );

							//console.log( shader.uniforms );
							//console.log( shader.vertexShader );
							//console.log( shader.fragmentShader );

						};

						mesh = new THREE.InstancedMesh( geometry, material, count );

						mesh.instanceMatrix.setUsage( THREE.DynamicDrawUsage ); // will be updated every frame

						scene.add( mesh );

					} );

				} );

				//

				stats = new Stats();
				document.body.appendChild( stats.dom );

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			//

			function animate() {

				requestAnimationFrame( animate );

				render();

				stats.update();

			}

			function render() {

				if ( mesh ) {

					const time = Date.now() * 0.001;

					mesh.rotation.x = Math.sin( time / 4 );
					mesh.rotation.y = Math.sin( time / 2 );

					let i = 0;
					const offset = ( amount - 1 ) / 2;

					for ( let x = 0; x < amount; x ++ ) {

						for ( let y = 0; y < amount; y ++ ) {

							for ( let z = 0; z < amount; z ++ ) {

								dummy.position.set( offset - x, offset - y, offset - z );
								dummy.rotation.y = ( Math.sin( x / 4 + time ) + Math.sin( y / 4 + time ) + Math.sin( z / 4 + time ) );
								dummy.rotation.z = dummy.rotation.y * 2;

								dummy.updateMatrix();

								mesh.setMatrixAt( i ++, dummy.matrix );

							}

						}

					}

					mesh.instanceMatrix.needsUpdate = true;

				}

				renderer.render( scene, camera );

			}

		</script>

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